Golf is enjoyed by a wide variety of players—players of different genders and players of dramatically different ages and skill levels. Golf is somewhat unique in the sporting world in that such diverse collections of players can play together in golf events, even in direct competition with one another (e.g., using handicapped scoring, different tee boxes, in team formats, etc.), and still enjoy the golf outing or competition. These factors, together with increased availability of golf programming on television (e.g., golf tournaments, golf news, golf history, and/or other golf programming) and the rise of well-known golf superstars, at least in part, have increased golf's popularity in recent years both in the United States and across the world.
Being the sole instruments that set golf balls in motion during play, golf clubs have been the subject of much technological research and advancement in recent years. For example, the market has seen improvements in designs of face plates, the overall golf club head, shafts, and grips in recent years. Additionally, other technological advancements have been made in an effort to better match the various elements and/or characteristics of the golf club and/or characteristics of a golf ball to a particular user's swing features or characteristics (e.g., club fitting technology, ball launch angle measurement technology, ball spin rate characteristics, etc.).
Golf clubs are designed to transfer the energy of the swung club to the golf ball. It is known that some amount of flex, or elastic deformation, of the club face is desirable to transfer this energy to the golf ball. The coefficient of restitution (COR) is a measure of this transfer. The COR of any typical conventional ball striking face is not constant across the face and is generally designed to be greatest at the desired impact region. Conventional ball striking faces, typically, have a lower COR closer to the perimeter areas where the ball striking face is joined to the rest of the club head body. In particular, certain iron-type golf heads have been designed so that the ball striking face has maximum flex. Such designs may include providing overall thinner ball striking faces, as well as thinning of select areas of the face. For example, in certain designs, the thicknesses of regions where the ball striking face is joined to the club head, such as at the sole or topline, have been reduced. Improving the COR across the ball striking face would provide the golf ball with a greater ball speed, which in turn would allow the ball to go farther. COR is also limited by the Rules of Golf as approved by the United States Golf Association.
However, as golfers tend to be sensitive to the “feel” of a golf club, technological improvements must take this into account. The “feel” of a golf club comprises the combination of various component parts of the club and various features associated with the club that produce the sensory sensations experienced by the player when a ball is swung at and/or struck. Club “feel” is a very personal characteristic in that a club that “feels” good to one user may have totally undesirable “feel” characteristics for another. Club weight, weight distribution, aerodynamics, swing speed, and the like all may affect the “feel” of the club as a golfer swings and strikes a ball. “Feel” also has been found to be related to the visual appearance of the club and the sound produced when the club head strikes a ball setting the ball in motion.
Accordingly, it may be desirable to improve the transfer of energy of the swung club to the golf ball, while at the same time providing a positive “feel” of the club to a golfer.